21071170100 has 36 divisors (see below), whose sum is σ = 45854046924. Its totient is φ = 8404577280.

The previous prime is 21071170093. The next prime is 21071170103. The reversal of 21071170100 is 107117012.

It can be written as a sum of positive squares in 6 ways, for example, as 74580496 + 20996589604 = 8636^2 + 144902^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21071170103) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 263159 + ... + 333758.

Almost surely, 2^21071170100 is an apocalyptic number.

21071170100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21071170100 is an abundant number, since it is smaller than the sum of its proper divisors (24782876824).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21071170100 is a wasteful number, since it uses less digits than its factorization.

21071170100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 597284 (or 597277 counting only the distinct ones).

The product of its (nonzero) digits is 98, while the sum is 20.

Adding to 21071170100 its reverse (107117012), we get a palindrome (21178287112).

The spelling of 21071170100 in words is "twenty-one billion, seventy-one million, one hundred seventy thousand, one hundred".